Preparation and characterization of stainless steel 316L/HA biocomposite

Biocomposites of stainless steel with a bioactive material, such as hydroxyapatite (HA), have been developed to improve the response in the tissue-implant interface as steel does not chemically bond with bone tissue. However, significant reductions in the mechanical properties of the biocomposite can occur. Different compositions of the biocomposite stainless steel 316L/HA (5, 20 and 50 wt% HA) were prepared by mechanical alloying. After milling the powders for 10 h, the different compositions of the biocomposite were compacted isostatically and sintered at 1200 C for 2 h. The mechanical properties of the biocomposites were analysed by compression tests. The powders and the sintered composites were analysed by SEM and XRD. It was found that composites with 20 and 50 wt% HA had higher porosity and thus lower strength. To maintain the strength of the biocomposite, the HA content should therefore be < 20 wt%.